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Installing uPVC Windows

Installing uPVC Windows

Here’s why installing uPVC windows is best left to us

We won’t cause mess and disruption to your home.

Interested in installing uPVC windows? First, we turn to award-winning companies like Roseview, Timberlook and VEKA. These leading manufacturers in uPVC windows and doors at affordable prices. Now, if you are thinking of replacing or upgrading your windows and doors throughout your house, you might be mistaken to think it’s going to be . . .


Expensive, time-consuming, messy and disruptive?

Well, Boyland Windows is pleased to tell you that you’re wrong. We’re not ones to usually say such things, but we’re going to delve into our process of installing uPVC windows. It’s a quick yet, by no means easy procedure to install a window with very little mess and disruption to your home.


Here’s how we might go about installing uPVC windows

We’ll takes you through our process – from start to finish.


Installing uPVC Windows | Step #1

Setting the scene.

Okay, imagine our fitters have removed your old windows and are prepping installing your new uPVC windows. It will look a little bit like this – brickwork around the outside and an opening where the old window was. You’re going to be able to see plasterboard from the inside of the interior between your cavity insulation. So, the new window will be fitted to the outside brickwork. Our suppliers will have fabricated the job offsite and delivered them to you.


Installing uPVC Windows | Step #2

Making the opening airtight.

Now, your fitters will start by measuring the intended window space. This is essential when installing uPVC windows. Then, what we’ll do, is install a windowsill to the bottom of the frame. Doing so will lift the frame. Meanwhile, our team will level it into position, screw and fix it to the brick on either side. We’ll also do this at the top and bottom. Then, once it’s in place, we’re going to put in expansion foam around its 5mm gap – right around the window – to make it airtight. Once set, we can take the beams out and fit the glass into position. Then when it’s fitted, we can use a silicone sealant around both the outside and the inside to fully seal it.


Installing uPVC Windows | Step #3

Cutting the sill down to size.

Whenever the windowsill arrives, it will be oversized – possible 100mm bigger. This is intentional for a specific reason. Some people prefer to have their windowsills flush with the edge of their wall on both sides. Whereas others prefer to notch out and scrape out the backend, leaving a thing called a horn. This horn will have sides that hang out beyond the brickwork. We think this looks aesthetically better, so we’ll fill you in on that method.

First, we use a pencil mark on one side of the sill that meets the wall. We then do the same again on the opposite side – just flush where the edge of the brickwork is. Then we place it in the front and leave equal-sized holes over both sides before putting another mark here. Using a set-square, we’ll draw a line where we’ve marked out the horn – but we’re going to set it back just a couple of mm for a bit of expansion room. We take our hacksaw and cut that off. Okay, so once you’ve cut one section off, just double-check you’re happy with that horn. If you are, then do the same on the opposite side.


Installing uPVC Windows | Step #4

Bringing the window together.

Now we’re one step closer to installing our uPVC windows. Turning the window upside down, we get the sill and clamp it on top – bearing in mind it should be upside down on here. We’re going to drill a couple of holes on each end and swap our drill out for a screwdriver. We’re going to drive two screws in there to hold it in position. Check that it’s flush on both sides and pressed down into position. However, you don’t want to do them too tight because you don’t want to distort the shape of the bottom of the shell.

Apply a small amount of silicon to both ends of the sill. This prevents moisture between the sill and the frame for when it’s in the brickwork. Now, we take some plastic patches – which are about 4mm high – place them on either side of the window opening. We then take the window, and this should hopefully fit nice and snug with that 5mm expansion gap right the way around the window – perfect!


Installing uPVC Windows | Step #5

Ensuring the window is level.

The next stage is to make sure that it is perfectly level and square to the opening of the window. With our spirit level in position, we double-check its level. Now, we can use a great little invention that’s like a little sleeve-like bag that slides into the corners – and we can pump them, and it starts to expand. Holding the frame in position, we don’t want to pump these bags too much as we don’t want to distort the frame. We just want them to hold it into position.

Okay, so once the window is steady, we double-check our spirit levels. We can easily make slight adjustments using the inflatable bags to square that window with the opening. Ensuring its level and the frame itself is nice and tight. We want it more or less touching the plasterboard on the inside, leaving about a 50mm gap set back off the face of the brickwork. Now, still leaving our little expansion gaps around the sides, and they’re going to be filled in later with foam and silicon.


Installing uPVC Windows | Step #6

Screwing the frame into position.

Okay, so now we’ve got the frame into position. The next step is to secure the window to the actual brickwork. So, we open our window – with the pump bags still holding it secure for us – and will drill some holes through the uPVC plastic frame. Then we’re going to screw through the frame and into the brickwork itself.

Regulations state that these should be fixed 150mm from the bottom and 150mm from the top. Now, if it’s a very small window, you can place one in the centre as well. We like to use three on each side. However, if your window is a lot bigger, you then need to space these out at 500mm apart.

Great – so that is our uPVC frame firmly fixed in with three fixings on each side. Now, if this window is a lot longer, you’d want to put further fixings in both the top and bottom to stop any flex if the wind was blowing against it. However, for educational purposes, we’re only installing a small window, so we’re just going to put one screw in the top and bottom of the frame.


Installing uPVC Windows | Step #7

Sealing the uPVC frame.

With the screws in place, we can remove the pump bags and use expanding foam. We’re going to foam all around both sides, including the top and the bottom of the frame, to make it airtight. However, we’re going to use a little bit of masking tape on the edge of the brickwork. This way, when the foam expands and oozes out, it’s not going to stick to the brickwork. Once that expands, it’ll draw down the side and stick inside the brickwork, making it a nice and airtight seal. Once it’s dry, we can trim that off with a trimming knife and then we can use a silicone sealant right the way around the outside to seal it.


Installing uPVC Windows | Step #8

Installing the glazing.

Once the expanding foam around the sides of the uPVC frame is dry and hard, we’re going to open the window and start on the glazing. First, we remove the glazing bands from the window and put them to one side – ensuring we know which side we’ve pulled them from.

For the next stage, we’ve got to ensure there’s no debris inside the actual window. To do that, we get these little glazing platforms to slip into the frame where the glass once was. Now, these work two ways. One, lifting the actual glazing panel itself up and then pushing them aside – and also along the top. It’s often called “toe and heeling” a window. This practice specifically allows any moisture that could build up around the glazing panel to weep out through the holes and onto the sill.

With all the window platforms in place, we very carefully lift the glass and place it in between here and – pressing it against the seals. Apply a small amount of pressure to the outside – double-check that it is nice and square to the actual frame itself. Then we’re going to start by putting the top glazing band in place to hold it to stop that glazing from actually toppling out.

We’re going to press this one in position – you will have to put a fair bit of pressure on them to start them off. Once it’s all in place, to better shift it into position, we’re going to use a nylon hammer. This way we can gently tap it until it completely closes and seals in. So, that’s one, and we then fit the bottom. With the glass fixed in position, we just double-check that we can still open and close the window still. Pushing on it is fine, and we can now pop the side pieces glazing bands in. With the sidebands installed, we can remove the little rubber bits from the glass that helped transport it and now it is glazed.


Installing uPVC Windows | Step #9

Finishing off your window’s aesthetics.

What we need to now do is start to remove some of the protective film around the outside. This will also be on the inside of the frames, which will need removing. We’ve left the protective seal on around the edges here at the moment. Some people prefer to take that off first and then run the gun down it. When they’re very confident and good with their gun, they’ll simply do it.

With the front of the window sealed with the silicone sealant and wiped down, we repeat the same on the inside. This includes the screw we used earlier to fix the centre bottom of the frame. We apply a small amount of silicon over the top, just to see a lot as well. It is that quick and easy to install uPVC windows. So, if you are looking for a way to put value on your house and make it more energy-efficient, why not get it right the first time with Boyland Windows?



Get in contact so we can start installing uPVC windows

First impressions are everything. Make yours count with Boyland Windows.

If we were to sum up Boyland Windows, we would say we are a solution provider for all your home improvement needs. We work with many product partners to supply you with the best possible option to use with your GOV Double Glazing Grant.


We cover:

Ashley – Barton on Sea – Boscombe – Bournemouth – Brockenhurst – Burley – Burton – Christchurch – Dorset – Ferndown – Hampshire – Highcliffe – Hurn – Lymington – Lyndhurst – Milford on Sea – Mudeford – The New Forest – New Milton – Poole – Ringwood – Southbourne – West Parley – Wimborne – Winton

At Boyland Windows, our friendly advisors can point you in the right direction for the best windows and doors. Have any further questions? We’re open Monday to Friday, 8 am – 4:30 pm.

Please feel free to get in touch by calling 01202 499499 or use our contact form.


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